android文件管理器用法详解
很久没有写东西了,鉴于某某同学文件管理器不会,这里简单介绍一下,同时写一个demon,参考了网上别人写的代码,自己也学习学习,研究研究。
首先所谓文件管理器,看起来就是一个列表,列表里面是文件夹或者文件,首先把布局写出来,我想在最上方的左边显示文件的路径,右边显示该路径下的文件个数,其实还是一个遍历文件,然后用列表显示出来的问题。下面是ListView,用来显示文件列表。下面是运行的效果图:
主界面的布局文件如下:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <RelativeLayout android:id="@+id/top" android:layout_width="match_parent" android:layout_height="wrap_content"> <TextView android:id="@+id/path" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_centerVertical="true" android:textSize="@*android:dimen/list_item_size" android:textColor="@android:color/white"/> <TextView android:id="@+id/item_count" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="@*android:dimen/list_item_size" android:textColor="@android:color/white" android:layout_alignParentRight="true" android:layout_centerVertical="true"/> </RelativeLayout> <View android:layout_width="match_parent" android:layout_height="2dip" android:background="#09c"/> <LinearLayout android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <ListView android:id="@+id/file_list" android:layout_height="match_parent" android:layout_width="match_parent" android:fadingEdge="none" android:cacheColorHint="@android:color/transparent"/> </LinearLayout> </LinearLayout>
首先在oncreate方法里面调用一个方法去获取布局文件里面的id:
@Override protected void onCreate (Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.file_manager); initView(); }
initView之后添加apk的权限,777 表示可读可写可操作。
private void initView() { mListView = (ListView) findViewById(R.id.file_list); mPathView = (TextView) findViewById(R.id.path); mItemCount = (TextView) findViewById(R.id.item_count); mListView.setOnItemClickListener(this); String apkRoot = "chmod 777 " + getPackageCodePath(); RootCommand(apkRoot); File folder = new File("/"); initData(folder); }
修改Root权限的方法:
public static boolean RootCommand (String command) { Process process = null; DataOutputStream os = null; try { process = Runtime.getRuntime().exec("su"); os = new DataOutputStream(process.getOutputStream()); os.writeBytes(command + "\n"); os.writeBytes("exit\n"); os.flush(); process.waitFor(); } catch (Exception e) { return false; } finally { try { if (os != null) { os.close(); } process.destroy(); } catch (Exception e) { e.printStackTrace(); } } return true; }
完了之后我们要获取根目录下面的所有的数据,然后设置到我们的ListView中让它显示出来。
private void initData(File folder) { boolean isRoot = folder.getParent() == null; mPathView.setText(folder.getAbsolutePath()); ArrayList<File> files = new ArrayList<File>(); if (!isRoot) { files.add(folder.getParentFile()); } File[] filterFiles = folder.listFiles(); mItemCount.setText(filterFiles.length + "项"); if (null != filterFiles && filterFiles.length > 0) { for (File file : filterFiles) { files.add(file); } } mFileAdpter = new FileListAdapter(this, files, isRoot); mListView.setAdapter(mFileAdpter); }
首先是获取当前是否是根目录,然后把文件的路径设置给我们要显示的View。
然后用一个ArrayList来装我们目录下的所有的文件或者文件夹。
首先要把这个文件夹的父类装到我们的列表中去,然后把这个文件夹下的子文件都拿到,也装在列表中,然后调用Adapter显示出来。既然说到了Adapter, 那就看下Adapter吧。
private class FileListAdapter extends BaseAdapter { private Context context; private ArrayList<File> files; private boolean isRoot; private LayoutInflater mInflater; public FileListAdapter (Context context, ArrayList<File> files, boolean isRoot) { this.context = context; this.files = files; this.isRoot = isRoot; mInflater = LayoutInflater.from(context); } @Override public int getCount () { return files.size(); } @Override public Object getItem (int position) { return files.get(position); } @Override public long getItemId (int position) { return position; } @Override public View getView (int position, View convertView, ViewGroup parent) { ViewHolder viewHolder; if(convertView == null) { viewHolder = new ViewHolder(); convertView = mInflater.inflate(R.layout.file_list_item, null); convertView.setTag(viewHolder); viewHolder.title = (TextView) convertView.findViewById(R.id.file_title); viewHolder.type = (TextView) convertView.findViewById(R.id.file_type); viewHolder.data = (TextView) convertView.findViewById(R.id.file_date); viewHolder.size = (TextView) convertView.findViewById(R.id.file_size); } else { viewHolder = (ViewHolder) convertView.getTag(); } File file = (File) getItem(position); if(position == 0 && !isRoot) { viewHolder.title.setText("返回上一级"); viewHolder.data.setVisibility(View.GONE); viewHolder.size.setVisibility(View.GONE); viewHolder.type.setVisibility(View.GONE); } else { String fileName = file.getName(); viewHolder.title.setText(fileName); if(file.isDirectory()) { viewHolder.size.setText("文件夹"); viewHolder.size.setTextColor(Color.RED); viewHolder.type.setVisibility(View.GONE); viewHolder.data.setVisibility(View.GONE); } else { long fileSize = file.length(); if(fileSize > 1024*1024) { float size = fileSize /(1024f*1024f); viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "MB"); } else if(fileSize >= 1024) { float size = fileSize/1024; viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "KB"); } else { viewHolder.size.setText(fileSize + "B"); } int dot = fileName.indexOf('.'); if(dot > -1 && dot < (fileName.length() -1)) { viewHolder.type.setText(fileName.substring(dot + 1) + "文件"); } viewHolder.data.setText(new SimpleDateFormat("yyyy/MM/dd HH:mm").format(file.lastModified())); } } return convertView; } class ViewHolder { private TextView title; private TextView type; private TextView data; private TextView size; } }
看下adapter的布局文件:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <TextView android:id="@+id/file_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="25sp" android:textColor="#fff000"/> <LinearLayout android:id="@+id/file_info" android:layout_width="match_parent" android:layout_height="wrap_content"> <TextView android:id="@+id/file_size" android:layout_width="0dip" android:layout_height="wrap_content" android:textColor="#ffffcc" android:layout_weight="1" android:textSize="18sp"/> <TextView android:id="@+id/file_type" android:layout_width="0dip" android:layout_height="wrap_content" android:textColor="#ffffcc" android:layout_weight="1" android:gravity="right" android:textSize="18sp"/> <TextView android:id="@+id/file_date" android:layout_width="0dip" android:layout_height="wrap_content" android:textColor="#ffffff" android:layout_weight="1" android:gravity="right" android:textSize="18sp"/> </LinearLayout> </LinearLayout>
列表的Item项分2行显示,上面一行显示文件名
下面一行分别显示文件大小,文件类型,文件修改时间。
我们可以通过File file = (File) getItem(position);拿到Item项的文件,如果是在第一个并且不再根目录我们就把第一个也就是parentFile显示为:“返回上一级”,下一行的都隐藏掉。
如果不是第一个位置,可以拿到这个文件的一系列信息。
先把String fileName = file.getName();文件名拿到,显示出来。
如果这个文件是一个文件夹,就把文件的大小显示为“文件夹”,类型和修改时间隐藏掉。
如果不是一个文件夹, 可以拿到文件的长度long fileSize = file.length();
根据特定的长度显示文件的大小,B, KB, MB, GB等。
然后拿到文件的类型,通过最后一个“.”之后的字符串就是该文件的类型。
通过viewHolder.data.setText(new SimpleDateFormat("yyyy/MM/dd HH:mm").format(file.lastModified())); 设置文件的最近修改时间。
然后可以设置每个Item项的点击事件,如下所示:
@Override public void onItemClick (AdapterView<?> parent, View view, int position, long id) { File file = (File) mFileAdpter.getItem(position); if(!file.canRead()) { new AlertDialog.Builder(this).setTitle("提示").setMessage("权限不足").setPositiveButton(android.R.string.ok, new OnClickListener() { @Override public void onClick (DialogInterface dialog, int which) { } }).show(); } else if(file.isDirectory()) { initData(file); } else { openFile(file); } }
如果这个文件不能读,就弹出对话框显示“权限不足”。
如果是一个文件夹,就在调用一次显示所有文件的方法:initData(file);把这个文件夹作为参数传递下去。
如果是一个文件,就可以调用打开文件的方法打开这个文件。
如何打开文件呢?
可以根据不同的文件的后缀名找到不同的文件类型:
可以用一个二维数组把一些常用的文件类型封装起来。如下:
private final String[][] MIME_MapTable = { // {后缀名, MIME类型} { ".3gp", "video/3gpp" }, { ".apk", "application/vnd.android.package-archive" }, { ".asf", "video/x-ms-asf" }, { ".avi", "video/x-msvideo" }, { ".bin", "application/octet-stream" }, { ".bmp", "image/bmp" }, { ".c", "text/plain" }, { ".class", "application/octet-stream" }, { ".conf", "text/plain" }, { ".cpp", "text/plain" }, { ".doc", "application/msword" }, { ".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" }, { ".xls", "application/vnd.ms-excel" }, { ".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" }, { ".exe", "application/octet-stream" }, { ".gif", "image/gif" }, { ".gtar", "application/x-gtar" }, { ".gz", "application/x-gzip" }, { ".h", "text/plain" }, { ".htm", "text/html" }, { ".html", "text/html" }, { ".jar", "application/java-archive" }, { ".java", "text/plain" }, { ".jpeg", "image/jpeg" }, { ".jpg", "image/jpeg" }, { ".js", "application/x-javascript" }, { ".log", "text/plain" }, { ".m3u", "audio/x-mpegurl" }, { ".m4a", "audio/mp4a-latm" }, { ".m4b", "audio/mp4a-latm" }, { ".m4p", "audio/mp4a-latm" }, { ".m4u", "video/vnd.mpegurl" }, { ".m4v", "video/x-m4v" }, { ".mov", "video/quicktime" }, { ".mp2", "audio/x-mpeg" }, { ".mp3", "audio/x-mpeg" }, { ".mp4", "video/mp4" }, { ".mpc", "application/vnd.mpohun.certificate" }, { ".mpe", "video/mpeg" }, { ".mpeg", "video/mpeg" }, { ".mpg", "video/mpeg" }, { ".mpg4", "video/mp4" }, { ".mpga", "audio/mpeg" }, { ".msg", "application/vnd.ms-outlook" }, { ".ogg", "audio/ogg" }, { ".pdf", "application/pdf" }, { ".png", "image/png" }, { ".pps", "application/vnd.ms-powerpoint" }, { ".ppt", "application/vnd.ms-powerpoint" }, { ".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" }, { ".prop", "text/plain" }, { ".rc", "text/plain" }, { ".rmvb", "audio/x-pn-realaudio" }, { ".rtf", "application/rtf" }, { ".sh", "text/plain" }, { ".tar", "application/x-tar" }, { ".tgz", "application/x-compressed" }, { ".txt", "text/plain" }, { ".wav", "audio/x-wav" }, { ".wma", "audio/x-ms-wma" }, { ".wmv", "audio/x-ms-wmv" }, { ".wps", "application/vnd.ms-works" }, { ".xml", "text/plain" }, { ".z", "application/x-compress" }, { ".zip", "application/x-zip-compressed" }, { "", "*/*" } };
分别对应的是后缀名和对应的文件类型。
我们可以根据文件的后缀名拿到文件的MIMEType类型:
private String getMIMEType(File file) { String type = "*/*"; String fileName = file.getName(); int dotIndex = fileName.indexOf('.'); if(dotIndex < 0) { return type; } String end = fileName.substring(dotIndex, fileName.length()).toLowerCase(); if(end == "") { return type; } for(int i=0; i<MIME_MapTable.length; i++) { if(end == MIME_MapTable[i][0]) { type = MIME_MapTable[i][1] ; } } return type; }
先遍历后缀名,如果找到,就把对应的类型找到并返回。
拿到了类型,就可以打开这个文件。
用这个intent.setDataAndType(Uri.fromFile(file), type); 打开设置打开文件的类型。
如果type是*/*会弹出所有的可供选择的应用程序。
到这里一个简易的文件管理器就成型了。
源代码:
package com.android.test; import java.io.DataOutputStream; import java.io.File; import java.text.DecimalFormat; import java.text.SimpleDateFormat; import java.util.ArrayList; import android.app.Activity; import android.app.AlertDialog; import android.content.Context; import android.content.DialogInterface; import android.content.Intent; import android.content.DialogInterface.OnClickListener; import android.graphics.Color; import android.net.Uri; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.BaseAdapter; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; public class FileManager extends Activity implements OnItemClickListener { private ListView mListView; private TextView mPathView; private FileListAdapter mFileAdpter; private TextView mItemCount; @Override protected void onCreate (Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.file_manager); initView(); } private void initView() { mListView = (ListView) findViewById(R.id.file_list); mPathView = (TextView) findViewById(R.id.path); mItemCount = (TextView) findViewById(R.id.item_count); mListView.setOnItemClickListener(this); String apkRoot = "chmod 777 " + getPackageCodePath(); RootCommand(apkRoot); File folder = new File("/"); initData(folder); } public static boolean RootCommand (String command) { Process process = null; DataOutputStream os = null; try { process = Runtime.getRuntime().exec("su"); os = new DataOutputStream(process.getOutputStream()); os.writeBytes(command + "\n"); os.writeBytes("exit\n"); os.flush(); process.waitFor(); } catch (Exception e) { return false; } finally { try { if (os != null) { os.close(); } process.destroy(); } catch (Exception e) { e.printStackTrace(); } } return true; } private void initData(File folder) { boolean isRoot = folder.getParent() == null; mPathView.setText(folder.getAbsolutePath()); ArrayList<File> files = new ArrayList<File>(); if (!isRoot) { files.add(folder.getParentFile()); } File[] filterFiles = folder.listFiles(); mItemCount.setText(filterFiles.length + "项"); if (null != filterFiles && filterFiles.length > 0) { for (File file : filterFiles) { files.add(file); } } mFileAdpter = new FileListAdapter(this, files, isRoot); mListView.setAdapter(mFileAdpter); } private class FileListAdapter extends BaseAdapter { private Context context; private ArrayList<File> files; private boolean isRoot; private LayoutInflater mInflater; public FileListAdapter (Context context, ArrayList<File> files, boolean isRoot) { this.context = context; this.files = files; this.isRoot = isRoot; mInflater = LayoutInflater.from(context); } @Override public int getCount () { return files.size(); } @Override public Object getItem (int position) { return files.get(position); } @Override public long getItemId (int position) { return position; } @Override public View getView (int position, View convertView, ViewGroup parent) { ViewHolder viewHolder; if(convertView == null) { viewHolder = new ViewHolder(); convertView = mInflater.inflate(R.layout.file_list_item, null); convertView.setTag(viewHolder); viewHolder.title = (TextView) convertView.findViewById(R.id.file_title); viewHolder.type = (TextView) convertView.findViewById(R.id.file_type); viewHolder.data = (TextView) convertView.findViewById(R.id.file_date); viewHolder.size = (TextView) convertView.findViewById(R.id.file_size); } else { viewHolder = (ViewHolder) convertView.getTag(); } File file = (File) getItem(position); if(position == 0 && !isRoot) { viewHolder.title.setText("返回上一级"); viewHolder.data.setVisibility(View.GONE); viewHolder.size.setVisibility(View.GONE); viewHolder.type.setVisibility(View.GONE); } else { String fileName = file.getName(); viewHolder.title.setText(fileName); if(file.isDirectory()) { viewHolder.size.setText("文件夹"); viewHolder.size.setTextColor(Color.RED); viewHolder.type.setVisibility(View.GONE); viewHolder.data.setVisibility(View.GONE); } else { long fileSize = file.length(); if(fileSize > 1024*1024) { float size = fileSize /(1024f*1024f); viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "MB"); } else if(fileSize >= 1024) { float size = fileSize/1024; viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "KB"); } else { viewHolder.size.setText(fileSize + "B"); } int dot = fileName.indexOf('.'); if(dot > -1 && dot < (fileName.length() -1)) { viewHolder.type.setText(fileName.substring(dot + 1) + "文件"); } viewHolder.data.setText(new SimpleDateFormat("yyyy/MM/dd HH:mm").format(file.lastModified())); } } return convertView; } class ViewHolder { private TextView title; private TextView type; private TextView data; private TextView size; } } @Override public void onItemClick (AdapterView<?> parent, View view, int position, long id) { File file = (File) mFileAdpter.getItem(position); if(!file.canRead()) { new AlertDialog.Builder(this).setTitle("提示").setMessage("权限不足").setPositiveButton(android.R.string.ok, new OnClickListener() { @Override public void onClick (DialogInterface dialog, int which) { } }).show(); } else if(file.isDirectory()) { initData(file); } else { openFile(file); } } private void openFile(File file) { Intent intent = new Intent(); intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); intent.setAction(Intent.ACTION_VIEW); String type = getMIMEType(file); intent.setDataAndType(Uri.fromFile(file), type); try { startActivity(intent); } catch (Exception e) { Toast.makeText(this, "未知类型,不能打开", Toast.LENGTH_SHORT).show(); } } private String getMIMEType(File file) { String type = "*/*"; String fileName = file.getName(); int dotIndex = fileName.indexOf('.'); if(dotIndex < 0) { return type; } String end = fileName.substring(dotIndex, fileName.length()).toLowerCase(); if(end == "") { return type; } for(int i=0; i<MIME_MapTable.length; i++) { if(end == MIME_MapTable[i][0]) { type = MIME_MapTable[i][1] ; } } return type; } private final String[][] MIME_MapTable = { // {后缀名, MIME类型} { ".3gp", "video/3gpp" }, { ".apk", "application/vnd.android.package-archive" }, { ".asf", "video/x-ms-asf" }, { ".avi", "video/x-msvideo" }, { ".bin", "application/octet-stream" }, { ".bmp", "image/bmp" }, { ".c", "text/plain" }, { ".class", "application/octet-stream" }, { ".conf", "text/plain" }, { ".cpp", "text/plain" }, { ".doc", "application/msword" }, { ".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" }, { ".xls", "application/vnd.ms-excel" }, { ".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" }, { ".exe", "application/octet-stream" }, { ".gif", "image/gif" }, { ".gtar", "application/x-gtar" }, { ".gz", "application/x-gzip" }, { ".h", "text/plain" }, { ".htm", "text/html" }, { ".html", "text/html" }, { ".jar", "application/java-archive" }, { ".java", "text/plain" }, { ".jpeg", "image/jpeg" }, { ".jpg", "image/jpeg" }, { ".js", "application/x-javascript" }, { ".log", "text/plain" }, { ".m3u", "audio/x-mpegurl" }, { ".m4a", "audio/mp4a-latm" }, { ".m4b", "audio/mp4a-latm" }, { ".m4p", "audio/mp4a-latm" }, { ".m4u", "video/vnd.mpegurl" }, { ".m4v", "video/x-m4v" }, { ".mov", "video/quicktime" }, { ".mp2", "audio/x-mpeg" }, { ".mp3", "audio/x-mpeg" }, { ".mp4", "video/mp4" }, { ".mpc", "application/vnd.mpohun.certificate" }, { ".mpe", "video/mpeg" }, { ".mpeg", "video/mpeg" }, { ".mpg", "video/mpeg" }, { ".mpg4", "video/mp4" }, { ".mpga", "audio/mpeg" }, { ".msg", "application/vnd.ms-outlook" }, { ".ogg", "audio/ogg" }, { ".pdf", "application/pdf" }, { ".png", "image/png" }, { ".pps", "application/vnd.ms-powerpoint" }, { ".ppt", "application/vnd.ms-powerpoint" }, { ".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" }, { ".prop", "text/plain" }, { ".rc", "text/plain" }, { ".rmvb", "audio/x-pn-realaudio" }, { ".rtf", "application/rtf" }, { ".sh", "text/plain" }, { ".tar", "application/x-tar" }, { ".tgz", "application/x-compressed" }, { ".txt", "text/plain" }, { ".wav", "audio/x-wav" }, { ".wma", "audio/x-ms-wma" }, { ".wmv", "audio/x-ms-wmv" }, { ".wps", "application/vnd.ms-works" }, { ".xml", "text/plain" }, { ".z", "application/x-compress" }, { ".zip", "application/x-zip-compressed" }, { "", "*/*" } }; }
最后补充一下,布局文件中的dimension是编译到jar包里面去了的,没有jar包的童鞋可以改成自己定义大小。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。
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